How to Build WSO2 Code

Although WSO2 is open source many people were having problem with checking out the WSO2 source code and building WSO2 products. Here are the simple steps to do it.
Note that at the moment ongoing development happens inside the trunk with version 4.2.0 SNAPSHOT. Last released WSO2 code is located in branch version 4.1.0 with Carbon platform version 4.1.2.

Build the trunk

1. Checkout Orbit from https://svn.wso2.org/repos/wso2/carbon/orbit/trunk/
2. Checkout Kernel from https://svn.wso2.org/repos/wso2/carbon/kernel/trunk/
3. Checkout Platform from https://svn.wso2.org/repos/wso2/carbon/platform/trunk/
4. Install Apache Maven 3 in your computer.
5. Go to the checked out directories and build with Maven of orbit, kernel and platform code respectively. (Use command, mvn clean install)
6. If any errors comes with tests use the command mvn clean install -Dmaven.test.skip=true
7. If the build is properly building and you are fortunate you will get all the products as zip files in each product. For example WSO2 BAM will be there in platform/trunk/products/bam/modules/distribution/target directory.
8. But most probably you will not be able to build all the products well at the same time and it will take much time as well. So you can build the product only you want as follows. Comment the products module in platform/trunk/pom.xml . Then after building all three orbit, kernel and platform, you can manually build the product/s you want. For example if you only want to build WSO2 BAM, go to platform/trunk/products/bam and build with command mvn clean install -Dmaven.test.skip=true

Build the Branch 4.1.0

1. Checkout orbit from https://svn.wso2.org/repos/wso2/carbon/orbit/branches/4.1.0/
2. Checkout kernel from https://svn.wso2.org/repos/wso2/carbon/kernel/branches/4.1.0/
3. Checkout platform from https://svn.wso2.org/repos/wso2/carbon/platform/branches/4.1.0/
4. Follow the exact steps 4, 5 and 6 mentioned under the topic, "Build the trunk".
5. In 7th step, use the directory path, branches/4.1.0/products/bam/2.3.0/modules/distribution/target as the BAM pack location.
6. Then follow the 8th step by commenting the product module in branches/4.1.0/pom.xml and building the BAM in location, branches/4.1.0/products/bam/2.3.0

Build a Tag

When already there is a released product, best way to build it, is by checking out the tag of the released version. The reason is that even the branch may be committed after the release by a mistake.

For this example lets continue with WSO2 BAM 2.3.0. It has orbit version 4.1.0, kernel version 4.1.0 and platform version 4.1.2. You can checkout these three from https://svn.wso2.org/repos/wso2/carbon/orbit/tags/4.1.0/ , https://svn.wso2.org/repos/wso2/carbon/kernel/tags/4.1.0/ and https://svn.wso2.org/repos/wso2/carbon/platform/tags/4.1.2/ . Then continue building in the same way as earlier.

Writing a Custom Mediator for WSO2 ESB - Part 3

This is the last part of blog post series about creating a WSO2 ESB mediator. Older parts are,

1. Part 1
2. Part 2

In this post I will explain the UI component of a ESB mediator using the BAM mediator (Carbon version 4.0.5). UI component (i.e.: org.wso2.carbon.mediator.bam.ui) is responsible for the BAM mediator specific UIs in the following UI.

Mediator UI

When BAM mediator is selected in the above mediator sequence (there is only the BAM mediator is available here anyway) the UI located under the sequence UI, is specified in the mediator UI component. Anyway not all the UI under it comes from the UI component. UI between the bar named Mediator and Update button comes from the UI component. Actually this is the edit-mediator.jsp JSP located in the resources package in org.wso2.carbon.mediator.bam.ui component.
After the changes are made on UI the user can click on the above mentioned Update button. This event will call the update-mediator.jsp JSP adjacent to the edit-mediator.jsp JSP.

When switch to source view is clicked the following source appears.

And you can return back to design view by clicking on switch to design view link. This toggling mechanism need the implementation of UI component. In simple terms this functionality need the implementation of,

1. BamMediator UI class - similar to BamMediator class in backend component
2. serialize method - similar to serializeSpecificMediator method in BamMediatorSerializer class in backend component
3. build method - similar to createSpecificMediator method in BamMediatorFactory class in backend component

Abstract Mediator Class (UI)

The difference of UI component with backend component is, that both serialize method and build method are included in the BamMediator UI class. BamMediator UI class can be found in org.wso2.carbon.mediator.bam.ui package.

BamMediator class should inherit from org.wso2.carbon.mediator.service.ui.AbstractMediator.

And also it should implement getTagLocalName method, similar to getTagQName used in backend. And also the serialize and build methods as mentioned earlier should be implemented.

public class BamMediator extends AbstractMediator {

    public String getTagLocalName() {

    }

    public OMElement serialize(OMElement parent) {

    }

    public void build(OMElement omElement) {

    }

}

Abstract Mediator Service Class

Every mediator UI component should consists of a Mediator Service class. In this example BamMediatorService is the class which implements the required settings of the UI. Let's explain with the example.

public class BamMediatorService extends AbstractMediatorService {

    public String getTagLocalName() {
        return "bam";
    }

    public String getDisplayName() {
        return "BAM";
    }

    public String getLogicalName() {
        return "BamMediator";
    }

    public String getGroupName() {
        return "Agent";
    }

    public Mediator getMediator() {
        return new BamMediator();
    }

}

As the example says every Mediator Service should inherit the org.wso2.carbon.mediator.service.AbstractMediatorService class.
Note how the name BAM is used as the sequence editor under the sub menu item named Agent. See how the getMediator method is used to execute the BamMediator UI class which we have discussed earlier.

Bundle Activator Class

Unlike other Carbon bundles where Bundle Activator is defined in the backend bundle, in a mediator class, the Bundle Activator is defined in the  UI bundle. In this example it is BamMediatorActivator class.

Basically the Bundle Activator should inherit the org.osgi.framework.BundleActivator class and should implement start and stop methods. For further information read this article.

Properties props = new Properties();

bundleContext.registerService(MediatorService.class.getName(), new BamMediatorService(), props);

Note how the BamMediatorService class is used.

Congratulations, you have finished the post series of how to write a custom mediator with WSO2 ESB. If you could not understand this well, most probably that is because you are not familiar with WSO2 Carbon platform. If you search more you will be able to catch them.